In-situ mining of ores from subsurface formations

ABSTRACT

An in situ method of mining is disclosed. In one non-limiting embodiment, the method includes: defining an ore volume; drilling a large number of vertical boreholes; forming lateral boreholes from at least some of the vertical boreholes; transporting the ore cut during drilling of the vertical and lateral boreholes to a surface location; and separating the ore received at the surface from other materials. Additional ore may be extracted fracturing and/or leaching the formation surrounding the drilled boreholes. The residual ore at the surface may be disposed by pumping it into already drilled boreholes or underground storage facilities.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application takes priority from U.S. Provisional application Ser. No. 62/074,493, filed on Nov. 3, 2014, which is incorporated herein in its entirety by reference.

BACKGROUND

1. Field of the Disclosure

The disclosure herein relates to in situ mining of ores from subsurface formations.

2. Background of the Art

Many high quality ore bodies are located at depths at which traditional mining methods, such as removal of overburden to extract the ore or creating mine stopes and shafts and using mining equipment or deploying humans are not feasible due to harsh environment or not economical to build open pits or underground mines. Also, a vast majority of the ore extracted, crushed and processed does not contain adequate amounts of the desired minerals. Also, current in situ leaching methods are limited to recover copper and uranium from ores. Also, very little sampling is currently performed in real-time. Such lack of information often results in ore rock being treated as waste. Many of the current mining methods also are not environmentally friendly.

This disclosure provides in situ methods of extracting ores from subsurface formations by drilling a large number of articulated boreholes through ore volumes and recovering additional ore from around the drilled boreholes utilizing fracturing and leaching of ores from around such boreholes.

SUMMARY

In one aspect, the disclosure provides a method of extracting ores from a subsurface location or an ore deposit without removing the overburden. In one embodiment the method includes: defining an ore volume; drilling a large number of mother-bores and forming lateral boreholes from the mother-bores; transporting the ore cut during drilling to the surface; separating the ore received at the surface; and extracting minerals from the separated ore at the surface. In another embodiment, the method further includes fracturing the drilled boreholes to recover additional ore. In another embodiment, the method further includes supplying a leaching fluid into drilled borehole to leach the ore surrounding the already drilled borehole and transporting the leached ore to the surface for recovery of the minerals contained therein.

Examples of the more important features of in situ mining have been summarized rather broadly in order that the detailed description thereof that follows may be better understood, and in order that the contributions to the art may be appreciated. There are, of course, additional features that will be described hereinafter and which will form the subject of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a detailed understanding of the apparatus and methods disclosed herein, reference should be made to the accompanying drawings and the detailed description thereof, wherein like elements are generally given same numerals and wherein:

FIG. 1A shows an in situ mining system utilizing a large number of boreholes for mining ore from a subsurface deposit or ore field;

FIG. 1B shows a plan view of another exemplary layout of large boreholes for mining ore;

FIG. 2 shows a schematic diagram of an exemplary drilling system that may be utilized for in situ mining of ores;

FIG. 3 shows an exemplary fracturing system for use with the in situ mining systems, including systems shown in FIGS. 1A and 1B;

FIG. 4 shows an exemplary leaching system for use with in situ mining systems, including systems shown in FIGS. 1A, 1B and 3; and

FIG. 5 shows an exemplary isolated subsurface ore bearing volume for mining ore therefrom according to the various methods of this disclosure.

DETAILED DESCRIPTION OF THE DRAWINGS

In general, the disclosure herein provides methods of defining or identifying an ore field located below the earth surface that includes an element of interest, extracting the ore by drilling a large number of boreholes through the ore field and processing of the extracted ore at the drill site to recover the element of interest from the extracted ore. FIG. 1A shows a borehole (or wellbore) system 100 that includes a large number of main or primary boreholes 102 a (also referred to as mother bores or mother wellbores) formed from the surface 101 through an overburden 104 and into an ore field or ore volume 106 (area or field or volume of interest) situated below or underneath the overburden 104 for the mining of ores (also referred to as minerals) from the ore field 106. The overburden 104 is the earth volume above the ore field 106. The boreholes 102 a may be formed in the area of interest 106 in any suitable pattern that would enable in situ mining of a substantial amount of ore from the ore field 106. In certain embodiments, the number of mother-bores may be very large, such as hundreds or thousands of boreholes, including vertical and non-vertical boreholes. In an exemplary embodiment, boreholes 102 a are shown as vertical boreholes drilled or formed from the surface 101 through the overburden 104 and into the ore field 106. Drilling through the overburden 104 avoids removal of the overburden 104 as typically done in conventional mining methods. Accordingly, in situ mining operations, i.e., mining without removing the overburden, compared to conventional mining where overburden is first removed, has less environmental impact and incur lower operational costs. Further, the use of in situ mining may allow for mining of ore or minerals from locations that are at depths, such as over 5000 feet, wherein conventional mining methods, such as forming mine shafts and employing large mining equipment therein to extract ore, is not practical or feasible due to high temperatures or excessive cost.

In some ore fields, the ore desired to be extracted 106 may be present in the form of distributed deposits. In other ore fields, the ore desired to be extracted may be deposited in veins. The methods described herein may be used to extract ore from all such deposits. In the exemplary ore field 106, some boreholes 102 a are shown to further include a number of lateral boreholes 108 a branched off from boreholes 102 a. Certain lateral boreholes 108 a further include one or more sub-lateral boreholes 110 a. Boreholes 102 a, lateral boreholes 108 a and sub-lateral boreholes 110 a may include boreholes of any suitable orientation, including vertical boreholes, deviated boreholes and horizontal boreholes formed in any direction. In aspects, the use of a large number of boreholes 102 a in conjunction with directional drilling, multiple kickoffs, trenchless drilling, and controlled drilling allow pin pointing deposits and veins containing desired elements and mining from such areas that were previously inaccessible for mining by conventional methods. Information from seismic surveys and pilot boreholes drilled through the ore field may be utilized to define an ore field, such as ore field 106. Defining an ore field may include developing the boundaries of the ore field 106 to develop a plan for the boreholes 102 a, 108 a and 110 a to maximize recovery of the ore from the ore field 106. Any borehole pattern may be utilized for in situ extraction of the ore from the ore field 106.

FIG. 1B shows a plan view of another borehole system 150, wherein vertical or main boreholes 152 a are formed according to a predetermined symmetric manner. Horizontal boreholes 154 a may be formed out from the vertical boreholes 152 a inside an ore field 116. Several horizontal boreholes 154 a may be formed from a single main borehole at different depths in the ore field 116, thereby forming a large number of horizontal lateral boreholes in the ore field 116 for in situ recovery of the ore. Any other borehole pattern containing a large number of boreholes may be utilized for the in situ ore recovery according to the methods described herein. Referring to FIGS. 1A and 1B, the main boreholes 102 a, 152 a may be relatively large, such as 28 inches or larger in diameter, lateral boreholes 108 a, 154 a may be 20 inches or larger in diameter, while sub-lateral boreholes 110 a may be 16 inches or larger in diameter. The spacing between adjacent boreholes may be selected to maximize the ore recovery while assuring stability of the boreholes being drilled and the boreholes already drilled. The stability criterion may be met if the bores do not collapse. In one aspect, the boreholes may be placed apart three times or more the diameter of the hole being drilled or the adjacent hole already drilled. In another aspect, the boreholes may be greater than five feet apart. The spacing between the boreholes may be selected based on the type of formation and the depth of the boreholes. Typically, a casing is installed at an upper section of each main borehole for surface stability for each main borehole. The main boreholes may be smaller as the wellbore depth increases. The methods disclosed herein enable recovery of ore from great depths, such as more than 15,000 feet, which is not feasible from conventional mining due to very high temperature and pressure at such depths. The methods described herein are useful for extracting ores that contain a variety of elements, including, but not limited to gold, silver, platinum, and copper. Sometimes, such elements are present in relatively narrow veins in subsurface formations. Such veins may be mapped using seismic images and pilot holes drilled. Boreholes may then be drilled through such veins using navigation techniques described later. Any suitable method of maintaining a desired distance between adjacent boreholes may be used, including magnetic ranging and acoustic ranging, known in the art.

FIG. 2 shows a schematic diagram of an exemplary drilling system 200 for drilling boreholes, such as boreholes 102 a, 108 a and 110 a shown in FIG. 1A for in situ mining of ores. The system 200 is shown drilling an exemplary borehole 202 by a drill bit 220 conveyed by drill string 228. The drill string 228 includes a drilling assembly 210 at a bottom of a tubular 212, such as made from connecting drill pipes or coiled tubing. The drill bit 220 is attached to the bottom of the drilling assembly 210 (also referred to as bottomhole assembly or “BHA”). The drilling assembly 210 includes a steering device 222 and a number of sensors commonly denoted by numeral 224 for steering the drill bit 220 along desired or selected borehole paths, such as borehole paths 108 a and 110 a. Such drilling is also referred to herein as “geosteering”. The drill bit 220 is rotated by a motor at the surface and/or by a drilling motor (not shown) in the drilling assembly 210 to drill the borehole 202 through an overburden 204 to an ore field or deposit 206. The drill bit 220 may be any suitable available drill bit. During drilling, the drill bit 220 cuts the deposit 206, creating ore cuttings (“ore”) 240. A drilling fluid 232 is supplied from the surface into the tubular 212, which fluid discharges at the bottom of the drill bit 220 and returns to the surface via annulus 214 between the drill string 228 and the borehole 202. The returning fluid (“return fluid”) 242 moves the cuttings 240 to the surface 201. Thus, the return fluid 242 is a mixture of the drilling fluid 232 and ore 240. As the drilling operations continue, cuttings 240 are continuously extracted from the ore field 206 and moved to the surface 201 by the return fluid 242. Thus, in the system 200, the ore 240 is broken underground (in situ) and moved to the surface without removing the overburden 204. The fluid flow 232 may be supplied into tubular 212 via fluid supply 230 facilities. Fluid 232 may include any suitable drilling fluid and may include lubricants and additives to facilitate the drilling and to transfer cuttings 240 to the surface 201.

In a non-limiting exemplary embodiment, drill bit 220 is steered by a steering device 222. The steering device 222 may include any available steering device, including, but not limited to, a device that includes a number of force application members that apply force on the inside of the borehole 202 to steer the drill bit 220 in the desired direction. In aspects, the sensors 224 provide information about the location of the drill bit 220 in the ore field 206 relative to a known location, such as true north. An operator and/or a control circuit or controller 260 in the drilling assembly 210 and/or a control circuit or controller 290 at the surface 201 may direct the steering device 222 to steer or maintain the drill bit 220 along the desired path. The controllers 260 and 290 may include processors, such as microprocessors, memory devices and programmed instructions for geosteering and to perform other downhole functions in real time. The controllers also may include circuits for processing measurements from the various sensors 224 to determine in real time the various properties of the constituents of the materials in the ore field 206. The sensors 224 also may provide information that enables the operator and/or the controllers 260 and/or 290 to maintain the drill bit 220 in the ore field 206. Thus, the sensors 224 provide information about elements in the ore and distances from the boundaries from subsurface faults and previously drilled boreholes. Such information may be utilized to maintain the drill bit in the desired ore zone and a desired distance from the previously drilled boreholes.

Sensors 224 may include a variety of sensors, including, but not limited to, accelerometers and magnetometers for providing the location and orientation of the drilling assembly 210 for geosteering. Sensors 224 may further include logging-while drilling sensors, including, but not limited to electrical sensors (such as resistivity sensors), electromagnetic sensors, acoustic sensors, nuclear logging sensors, elemental spectroscopy sensors, and pulsed neutron sensors. The sensors 224 may be characterized for a particular mineral or element of interest. For example, for a pulsed neutron sensor, peaks may be calibrated based on the mineral or element of interest in a particular ore field 206, such as copper, uranium, gold, manganese, nickel, and rare earths to provide optimal detection of such minerals. Downhole logging tools exist that perform pulsed neutron elemental analysis wherein the formation is temporarily irradiated with neutrons, which strike the nuclei of elements, which subsequently emit radiation including gamma rays of various energies whose unique spectral fingerprints then allow identification and quantification of those elements. Even when there is spectral overlap, it is possible to distinguish one spectrum from another because different radioisotopes have different half-lives so one can wait to collect spectral data until after radiation from an interfering species has decayed away. The sensitivity of this technique depends upon the element. Tables of sensitivities for various elements are well known. Therefore, operators can geosteer along a vein of a precious metal or some other element by performing real time elemental analysis. Downhole elemental analysis might also be performed by focusing a laser or a spark on cuttings lying just outside of an optical window analogous to the elemental analysis of a fluid by laser induced breakdown spectroscopy (LIBS) and spark-induced breakdown spectroscopy (SIBS) described in U.S. Pat. No. 7,530,265, which is incorporated herein by reference in its entirety. In another method of drilling a borehole through an identified vein containing a metal, such as gold, platinum, etc., a resistivity sensor in the BHA may be used to determine in real time the resistivity of the formation surrounding the borehole and in front of the drill bit. Such sensors can provide relatively accurate information relating to the presence of metals and concentrations levels in the ore. This information may be utilized to maintain the drill bit 220 in the vein containing the selected ore. In other embodiments, alternative sensors may be used to find other materials, such as platinum and diamonds. Information from sensors 224 may also provide rock type identification and correlation, rock mass characterization, litho-stratigraphic interpretation, ore body delineation, grade estimation, etc. The measurements from the sensors 224 may be processed by the downhole controller 260 to determine the various properties of the ore and the rock and to take actions, such as geosteering. Alternatively, or in addition thereto, information from the sensors 224 may be telemetered to the surface controller 290, which may process such information and take actions. Any suitable telemetry system may be used, including, but not limited to mud pulse telemetry, electromagnetic telemetry, or electrical conductors or optical fibers in the drill string 228. A telemetry device 292 in the drilling assembly 210 may provide two-way communication between the controllers 260 and 290. For ore processing at well site, small conventional smelting or leaching units may or more environmentally friendly bioleaching units may be set up at the rig site.

As the return fluid 238 is received at surface 201, the ore 240 (cuttings) may be separated from the fluid 232 and processed or partially processed near the rig site 201. In an exemplary embodiment, a separator 234 separates the ore 240 from fluid 232. An ore processor 236 may further refine the separated ore 240 into a material or form suitable for transportation away from in situ mining system 200. The ore processor may include a smelter, for example, for extracting a metal from the ore, a chemical processing unit for leaching the desired element from the ore or any other facility suitable for extracting the desired elements from the ore 240. In general, the amount of the desired element in the ore is often less than one percent by weight or volume. The ore or material remaining after processing (the “discarded material” or “residue ore”) may be disposed in any suitable manner. In certain embodiments, a disposal unit 238 receives and stores residue ore. In certain other embodiments, a disposal unit 238 recycles or reintroduces the residue ore into one or more boreholes already drilled or into an underground facility formed to store such undesired material. The ore residue may be mixed with a suitable fluid, such as water and pumped into the boreholes or storage facilities or contained by other known disposal methods including pumping cement and residual cuttings back into the boreholes. The ore recovery methods described in reference to system 100 of FIGS. 1A and 1B and system 200 of FIG. 2 enable in situ recovery of ores during drilling of boreholes 102 a, 108 a and 110 a through the ore field or volume 106. The remaining ore in the field 106 or a portion thereof may recovered by secondary operations or methods that may include leaching the ore surrounding some or all boreholes 102 a. 108 a and 110 a or fracturing the ore around such boreholes and then leaching the fractured ore, as described in more detail in reference to FIGS. 3 and 4.

FIG. 3 shows an exemplary non-limiting system 300 for fracturing (also referred to as fracing) for use with in situ mining systems, including system 100 of FIG. 1A and system 150 of FIG. 1B. In aspects, the use of the fracturing system 300 with in situ mining systems, such as system 100 enables recovery of additional ore from the mineral deposit or ore field 106. For simplicity, the system 300 is shown to include a single main borehole 351 formed in an ore field 306 and lateral boreholes 353 a and 353 b formed from the main borehole 351. In general, an area or a zone around a borehole may be fractured by supplying a treatment fluid (also referred to as the frac fluid) 349 from a source 350 under pressure to create the fractures in such zone. The fluid 349 may contain a proppant, such as sand or synthetic beads. In the non-limiting exemplary system 300, to fracture a zone Z around the borehole 353 a, perforations 352 may be created to facilitate the fracing operations. Perforations 352 may be created by any suitable method, mechanism or technique, including, but not limited to, perforating guns. Perforations 352 may facilitate cracking or fracturing of the formation around the borehole 353 a. In certain embodiments, zones of interest to be fractured may be isolated with isolation devices 356 prior to fracing operations. Isolation devices 356 enable the fluid 349 to be contained between the isolation devices 356 and create fractures 354 in a desired area. Isolation devices 356 may further isolate other downhole fluids from migrating to other areas, as well as preventing frac fluid 349 from migrating to other areas. In an exemplary embodiment, frac fluid 349 is pumped from a frac fluid source 350 to exert pressure upon deposit 306 and perforations 352. The frac fluid 349 may be any suitable treatment fluid, and may include components such as water, sand, guar, synthetic beads, lubricants, and other additives. As the frac fluid 349 pressure builds up in the wellbore 353 a, fractures 354 tend to propagate through the deposit 306. Fractures 354 allow removal of more of the deposit 306 because they create a greater surface area to be exposed for leaching operations described herein. In other embodiments, explosives are utilized to fracture ores surrounding the boreholes.

FIG. 4 shows an exemplary non-limiting leaching system 400 for use with an in situ mining system, such as system 100 of FIG. 1A. The system 400 is shown to include a main borehole 451 formed in an ore field 406 and lateral boreholes 408 a and 408 b formed from the main borehole 451. In the system 400, to leach a section of a borehole, such as borehole 408 a, a leaching fluid 466 is supplied into borehole 408 a via a tubing (not shown). The leaching fluid flow 466 may be supplied into borehole 408 a from a leaching fluid source 464 at the surface 401. Leaching fluid source 464 may supply any suitable fluid including any suitable chemicals for leaching the particular underground deposits, including appropriate lixiviates for various materials, such as copper, uranium, and other suitable materials. As leaching fluid 466 is introduced to deposit 406 and corresponding ore, leaching fluid 466 liquefies deposit 406 which dissolves in the leaching fluid 466. Thus, the leaching fluid 466 becomes impregnated with the chemically reacted ore deposit 406 and allows greater yields and movement of the ore. In certain embodiments, borehole 402 is fractured via a fracturing process (as previously described) to allow leaching fluid 466 to interact with fractures 454. The fractures 454 allow a greater surface area for interaction with leaching fluid 466. In other embodiments, leaching may be performed without prior fracturing of the boreholes. The impregnated leaching fluid 468 may be brought to the surface 401 by any suitable method, including by natural pressure differential or artificial lift mechanisms. Recovered fluid 468 may be received by a leaching fluid processor 462. In an exemplary embodiment, leaching fluid processor 462 removes the dissolved or liquefied deposits 406 from the impregnated solution 468. In certain embodiments, the leaching fluid processor 462 removes all or a portion of the desired material from the fluid 468. In certain embodiments, the recovered fluid 468 is stored in leaching fluid storage 460. The stored fluid may be isolated, partially isolated, chemically altered or otherwise processed.

FIG. 5 shows an exemplary non-limiting isolation system 500 for use with in situ mining or other mining systems. In an exemplary embodiment, isolation system 500 utilizes naturally occurring or preexisting fracture planes 570 to create isolation volumes 510. In certain embodiments, preexisting fracture planes 570 are created during prior fracturing operations, such as those described in system 300. In certain embodiments, fracture planes 570 are found via seismic surveys. In other embodiments, acoustic measurements from downhole sensors may be utilized to confirm and determine the location of fracture planes 570. In an exemplary embodiment, computer simulations and other methods may be utilized to place fractures 554 and locate fracture operations to allow for desirable fracture propagation 572. Fracture propagation 572 allows for isolated volumes to be formed. In an exemplary embodiment, isolated volumes along propagated fractures 572 allows for volumes to be isolated for future fracture operations, such as those described in FIG. 3 In an exemplary embodiment, fracture operations are facilitated as described in FIG. 3, by providing adequate fluid pressure from fluid source 550.

In one embodiment, the isolated volume may be subjected to additional operations. The isolated volume may be subjected to in situ mining methods, fracturing methods, and leaching methods as described above. In certain other embodiments, traditional mining methods are used. In an exemplary embodiment, mine shaft 574 is formed and utilized to allow the ore inside to be retrieved. In alternative embodiments, in situ mining methods are utilized.

Thus in some aspects, the disclosure provides various methods of extracting ores from a subsurface location or the ore field without removing the overburden, i.e., without removing the earth material from above the ore field. In one method the ore volume or field may be defined or mapped from seismic surveys and/or from pilot or test wells drilled into the subsurface. The ore field may be several hundreds of feet (such as over 500 feet) or several thousand feet (such as over ten thousand feet) below the surface. The ore field may be relatively large, such more than ten miles wide, more than 20 miles long and more than 1,000 feet deep. In one non-limiting embodiment the method may further include developing a well plan that may include a very large number of vertical wells, such as a few hundred to a few thousand wells, some or all of the wells further including one or several lateral wells. The wells (vertical wells and lateral wells) are formed using drilling assemblies that include a drill bit, a steering device, sensors for providing the location of the drill bit, sensors for providing information about the ore desired to be recovered while drilling and a telemetry device that allows real time communication between the drilling assembly and a surface location. The wells are drilled by circulating a drilling fluid that discharges at the drill bit bottom and returns to the surface via an annulus between the drill string and the well. The ore drilled or disintegrated by the drill bit travels to the surface with the drilling fluid. The ore in the returning fluid is separated from the drilling at the surface. If a very large number of wells (such as several thousand) are drilled into the ore field, a substantial volume of the ore from the ore field may be recovered from the ore field without reducing or eliminating the overburden. Such a method is safe relative to conventional mining methods as it does not involve forming large shafts and transporting mining equipment or persons into the mines. Measurements from the sensors are used to geosteer, i.e., drill the wellbores along desired paths. In other method, some or all drilled wellbores may be treated, such as fractured and/or leached to recover additional ore from the ore field. In another aspect, a subsurface zone containing a desired ore may be isolated. Such zone may then be fractured and used for in situ mining according to the methods described herein and/or traditional mining methods, such as using mine shafts.

The foregoing disclosure is directed to the certain exemplary non-limiting embodiments of in situ mining methods and systems. Various modifications will be apparent to those skilled in the art. It is intended that all such modifications within the scope of the appended claims be embraced by the foregoing disclosure. The words “comprising” and “comprises” as used in the claims are to be interpreted to mean “including but not limited to”. Also, the abstract is not to be used to limit the scope of the claims. 

1. A method of in-situ mining of ore from below the earth surface without removing overburden, the method comprising: defining an ore volume below the surface of the earth; drilling a plurality of boreholes from a surface location through the ore volume to disintegrates the ore volume, wherein each wellbore is drilled by a rotating a drill bit attached at bottom of a drill string and wherein a fluid is circulated through the drill string and the wellbore fluid returning (“return fluid”) to the surface carries therewith the ore disintegrated by the drill bit; and processing the return fluid at the surface location to recover a selected element present in the ore in the return fluid.
 2. The method of claim 1 further comprising defining the ore volume using at least one of: seismic survey of earth subsurface that includes the ore volume; information relating to previously drilled boreholes; and acoustic ranging.
 3. The method of claim 1, wherein drilling the plurality of boreholes includes maintaining in place the overburden above the ore volume.
 4. The method of claim 1, wherein the plurality of boreholes are drilled using pad drilling, wherein each borehole in the plurality of boreholes is drilled from a common surface location and the ore volume from all the return fluid is processed at the common surface location.
 5. The method of claim 1, wherein drilling the plurality of boreholes comprises: drilling a plurality of main boreholes; and drilling one or more lateral boreholes for at least some of the main boreholes.
 6. The method of claim 1, the method further comprising: fracturing formation surrounding at least some of the boreholes in the plurality of boreholes; and extracting ore from the fractured formation.
 7. The method of claim 1 further comprising; leaching formation surrounding at least some of the boreholes in the plurality of boreholes to produce fluid that contains the ore; and extracting an element of interest from the fluid that contains the ore to the surface.
 8. The method of claim 1, wherein the ore field is more than 5000 feet deep and the plurality of boreholes includes at least one hundred boreholes, wherein each borehole is spaced less than one hundred feet from an adjacent borehole.
 9. The method of claim 1, wherein each borehole is between five feet and twenty five feet from at least one borehole.
 10. The method of claim 1, wherein the plurality of boreholes includes a first plurality of vertical boreholes, each such borehole being larger than 28 inches in diameter; at least one lateral wellbore formed from at least some of the main boreholes, each such lateral bore hole being larger than eighteen inches in diameter.
 11. The method of claim 1, wherein the ore volume is an isolated section formed by fracture planes created by fracturing of the earth subsurface.
 12. The method of claim 1 further comprising identifying an element of interest in the ore volume during drilling of at least one borehole in the plurality of boreholes using one of: a pulsed neutron sensor calibrated for a peak relating to a mineral of interest.
 13. The method of claim 14, wherein the element of interest is selected from a group consisting of: copper; uranium; gold; platinum; nickel; and manganese.
 14. The method of claim 1 further comprising determining quantity of an element of interest from the ore separated from the return fluid.
 15. The method of claim 1 further comprising maintaining drilling of a particular borehole in the plurality of boreholes a selected distance from any other borehole already drilled.
 16. The method of claim 15, wherein maintaining the selected distance comprising using one of: acoustic logging while drilling; and magnetic ranging while drilling.
 17. The method of claim 1 further comprising disposing ore remaining after processing (“residue”) as one of: pumping the residue with a fluid into one or more boreholes already drilled; pumping the residue with cement into one or more boles already drilled; and storing the residue in underground storage units.
 18. A method of in-situ mining of an ore from below the earth surface from a vein containing a metal of interest, the method comprising; defining the vein containing the metal of interest; drilling a borehole from a rig site through the vein to disintegrate ore in the vein into cuttings by circulating a fluid through the borehole; geosteering the drilling of the borehole using an electrical measurements of surrounding the borehole during drilling to maintain the borehole within the vein; receiving a return fluid from the borehole containing the cuttings; separating the cuttings from the return fluid; and processing the cuttings at the rig site to recover the metal of interest from the cuttings.
 19. The method of claim 18, wherein the electrical measurements are responsive to metallic elements present in the formation surrounding the borehole and the formation in front of the borehole.
 20. A system for in-situ mining of ore from an ore volume below the earth surface without removing overburden, the system comprising: a drilling system for drilling a plurality of boreholes from a rig site that uses a fluid to drill the plurality of boreholes and receives a return fluid from each such borehole that includes cuttings of the ore therein; a separator at the rig site that separates the ore cuttings from the return fluid; and a processing unit at the rig site that processes the separated ore cutting to recover an element of interest from the ore cuttings. 